title: A new type of wide-field horizontal cell, presumably linked to blue cones, in rabbit retina.
abstract: Horizontal cells of vertebrate retina play an important role in the formation of visual receptive field surrounds of bipolar cells, and hence in the centre-surround receptive field organization of retinal ganglion cells. In some retinas, horizontal cells also play a major functional role in the first stage of colour-coding of visual stimuli. We have identified a new type of horizontal cell, called 'type C', in rabbit retina, which unlike type A and type B horizontal cells, contacts only a small fraction of cone photoreceptors, possibly blue cones. The multiple, sparsely branched axons of type C cells are well-positioned to contact bipolar dendrites in a feedforward manner. In summary, we propose (1) that the presence in rabbit retina of 3 types of cone horizontal cell, A, B, and C, may represent a more common pattern in mammalian retinae, shared with many non-mammalian retinas which contain colour-coded neurons, (2) that type C cells connect principally to blue cones, and (3) that type C cells are more common in retinas, such as those of squirrels, and to a lesser extent rabbits, in which blue cones play a major role in the colour coding of visual signals.
authors.affiliation: Lions Sight Centre, University of Calgary Faculty of Medicine, Alta., Canada.
authors.forename: E V
authors.initials: EV
authors.lastname: Famiglietti
mesh_terms: D000818:Animals; D010786:Photoreceptor Cells / Q000502:physiology*; D011817:Rabbits; D012160:Retina / Q000166:cytology* / Q000502:physiology; D014795:Visual Pathways / Q000502:physiology